Internal combustion engine



Jan. 15, 1935. C' LATTA I l 1,988,082

-` INTERNAL COMBUSTION ENGINE I Filed Sept. 2, 1930 6 Sheets-Sheet l n Jan. l5, 1935. c. LATTA INTERNAL GOMBUSTION ENGINE Filed sept. 2A, 195o' 6 Sheets-Sheet 2 Jan. 15, 1935. c. LATTA 1,988,082

INTERNAL COMBUSTION ENGINE Filed Sept. 2, 1930 6 Sheets-Sheet 5 lill! l, m m m Jan. 15, 1935. c. LATTA 1,988,082

INTERNAL COMBUSTION ENGINE ,Filed Sept. 2, 1930 6 `Sheets-Sheet 4 Jan. 15, 1935. c. LATTA 1,988,082

` INTERNAL COMBUSTION ENGINE Filed Sept. 2, 1930 l 6 Sheets-Sheet 5 IIIIII lll/,L

Jan. 15, 1935. f c; LATTA 1,988,082

INTERNAL COMBUSTION ENGINE Filed Sept.. 2, 1950 6 Sheets-Sheet 6 'S-ig -15- Fig 15- 17.

Fig 15- Patented Jan. 15, 1935 UNITED STATES ATiEilt'l' OFFICE 3 Claims.

This invention relates to internal combustion engines; and an object is to produce an internal combustion engine comprising improved means for breaking up and atomizing heavy fuel oils, as

5 distinguished from the usual volatile liquid fuels, automatically and during the passage oi the fuel oils from a carburetor to the combustion cylin ders, so that heavy fuel oils may be used with the same advantages as the volatile liquid fuels in engines of other construction.

Another object of the invention is to provide an internal combustion engine comprising pumps for effecting and controlling the passage of atomized fuel oil toward the combustion cyl inders, and valves arranged to cooperate with the respective pumps to control and regulate the admission of rthe fuel to the pumps and the discharge oi the fuel from the pumps and into the combustion cylinders, and means for controlling said valves to break up and atomize heavy fuel oil in order to obtain more perfect combustion in the combustion cylinders of the engine.

Another object of the invention is to provide an improved internal combustion engine comprising a number of working or combustion cylinders, and a corresponding number of pumps through which the fuel must pass to enter the combustion cylinders, a series of valves arranged to atomize or partly atomize and control the admission of the atomized or partly atomized fuel oil to the pumps and the discharge of the atomized oil from the pumps, and another series of valves for completing the atomization of the fuel oil and for controlling the circulation and passage of the atomized oil toward and into the combustion cylinders, all of said cylinders, pumps and valves operating and cooperating in such a way that heavy oils may be utilized as fuel instead of the 'usual liquid fuel.

Other objects will appear from the following description, reference being made to the accom-v (Cl. 12S- 59) approximately on the line Ll---l of Fig. 3, showing the piston down to permit exhaust.

Fig. 5 is a similar sectional view showing the piston up on compression.

Fig. 6 is ay vertical cross sectional view approximately on the line 6-6 of Fig. 1, showing the pumpA and the outlet valve therefrom open.

Fig. 'l is a vertical cross sectional view on the line 7-7 of Fig. l, showing the pump and the inlet valve thereto closed.

8 is a cross sectional view onthe line 8*-8 of Fig. l, showing another pump device and the open inlet valve thereto.

Fig. 9 is a cross sectional view, approximately on the line 9 9 of Fig. l, showing the pump of Fig. 8 and the closed outlet valve therefrom.

Fig. 10 is a View of an engine, partly in section, embodying additional valves for breaking up and atomizing the fuel oil suitable for use in'an engine having the cranks for the pistons H and the pump devices at 180 angles from the aXis of the crank shaft.

Fig. 11 isa sectional View, approximately on the line 11--11 of Fig. l0, showing the valve at the working cylinder.

Fig. 12 is a diagrammatic View of the connectionsfor operating the pistons and pumps of an engine in which the cranks for the pistons and pumps are relatively 180 apart.

Fig. 13 is a vertical longitudinal sectional view of an engine having the piston and pump cranks 180 apart. o

Fig. 14 is a plan view, with parts in section, oi the engine body with the head of the engine removed.

Fig. 15 is a vertical cross sectional view, approximately on the line 15-15 ofV Fig. 10, showing the valve that controls the passage of gas from the pump in closed position.

. Fig. 16 is a vertical cross sectional'view on the line 16-16 of Fig. l0, showing the inlet valve to the pump in open position.

Fig. 17 is a vertical cross sectional view on the line 17-17 of Fig. 10, showing the inlet valve to the pump in closed position.

Fig. 18 is a vertical cross sectional view on the line 18-18 of Fig. 10, showing the outlet valve from the pump in open position.

Fig. 19 is a vertical cross sectional View on the line 19-19 of Fig. 10, showing the inlet valve to the work cylinder in open position.

The engine shown in Figs. 1 to 9, inclusive, comprises a crank shaft 1 provided with a number of cranks connected with the pistons of the engine. and also provided with a number of cranks connected with the pump devices. There is one pump device for each engine piston and the cranks 2 and 3 for the pumps are at angles of 90 from and ahead of the cranks 4 and 5 of the pistons with which the respective pumps correspond and cooperate. That is, the pump crank 2 operates a pump that pumps fuel to the cylinder corresponding to the crank 4, and the crank 3 operates a pump for the cylinder that corresponds to the crank 5. The crank 4 is operatively connected by a connecting rod 6 with a working piston 7 mounted in a cylinder 8, and the crank 5 is operatively connected by a connecting rod 9 with a working piston 10 mounted in a cylinder 11.

In the embodiment shown the pumps oomprise pistons operating in cylinders communieating with the respective cylinders 8V and 11 through valve controlled passages. The valves perform the double function of controlling the passage of fuel to the pumps and thence to the workingv cylinders, and also braking up and atomizing the heavy fuel and the heavy ends of the fuel, so that this engine will operate with heavier fuel than engines of ordinary construction. I have satisfactorily used heavy fuel oil with results as good as can be obtained in any engine known to me that uses the volatile fuels. For the working cylinder 8, there is a pump piston 12 mounted in a cylinder 13 (Figs. 8 and 9) and connected with the crank 2 by a connecting rod 14. For the working cylinder 11 there is a pump piston 15 mounted in a cylinder 16 (Figs. 6 and 7) and connected with the crank 3 by a connecting rod 17. Thus, the crank shaft 1 is rotated by the working pistons 7 and 10, and said crank shaft operates the pump devices comprising the pistons 12 and 15. It is clear enough that the number of working pistons and corresponding pumps may be varied toA theV extent desired without departure from` the invention. The illustrated construction is merely an exemplification of an embodiment of the invention and is not a limitation in these or other unessential particulars.

A carburetor 18 of any known or standard construction is provided with an inlet 19. An outlet pipe 20 from the carburetor communicates through an opening 21 with a manifold 22 (Fig. 3). The manifold 22 opens toward the pump cylinder 13 through a passage 23 and opens toward the pump cylinder 16 through a passage 24. The top or head member 25 of the engine is formed with combustion chambers 26 above and communicating with the respective working cylinders 8 and 11; and is formed with chambers 27, which are of less capacity than the chambers 26, above and communicating with the respective pump cylinders 13 and 16 in communication with the ports 23 and 24 (Fig. 2). The difference in the capacity of the chambers 27 with respect to the chambers 26 is obtained by making the chambers 26 of greater height than the chambers 27 (Fig. 3.) From the pump cylinder 13 the chamber 27 opens through the port 28 into a passage 29 which communicates with a passage opening into the Working cylinder 8 through spaced ports 31. The port 28 is of less capacity and size than the port 23 and the passage 29 tapers toward its end that opens into the passage 30 from which the ports 31 form restricted inlet ports to the cylinders 8. The passage 30 is of no greater capacity than the end of the passage 29 connected thereto. The ports 31 are separated by a wall portion 32 of the cylinder 8 which functions to jet the atomized fuel into the working cylinder 3 and also functions as a slide surface for the piston rings.

A poppet valve 33 is operative to open and close the port 23 and to form a baffle across and around which the partially atomized fuel must pass to enter the pump for the cylinder 8. This valve functions also to increase the atomization of the partially atomized fuel. The stem 34 of the valve 33 is actuated downwardly by a spring 35, as clearly shown, and has its lower end engaging the upper end of a push rod 36. The lower end of the rod 36 engages a cam 37 attached to the cam shaft 38. This cam 37 has a low side extending about 180 and curving to the highest point, so that said cam will begin to open the valve 33 at the beginning of the rise on thc cam and will open the valve fully at the highest point of the cam, and then permit the valve to move toward closed position until the low point of the cam is reached. Thus the cam 37 functions through 180 thereof, first to move the valve: 33 toward open position and then to permit the valve to move toward closed position, so that said valve is partly open through 180 of said cam 37. The stern 34 and push rod 36 are operative in guides 39. The cam shaft 38 is journaled in bearings 40 in the engine body and in a bearing 41 supported by a removable end plate 42 attached to the front end of the engine. A gear wheel 43 attached to the cam shaft 38 meshes with a gear wheel 44 attached to the crank shaft 1, so that said cam shaft is driven by and at the same speed as the crank shaft.

The port 28 is controlled by a poppet valve 45 attached to a sliding stem 46 and actuated downwardly by a spring 48. The lower end of the valve stem 46 engages the upper end of a push rod 49 bearing against a cam 50 attached to the cam shaft 38'. The stern 46 and push rod 49 operate in guides 47. The relative arrangement of the cams 37 and 50 is such that the high points of said cams are on different radii, so that the valves 33 and 45 are never opened at the same time, but both valves are closed at the same time. The high point of the cam 37 extends in the same direction as the crank 4 for the working piston, and the high point of the cam 50 extends angularly with respect to the said crank 4.

The radius of the high point of the cam 37 is at right angles to the radius of the corresponding pump crank 2 (Figs. 7 and 8). The cam 37 begins to open the valve 33 at the beginning of the down stroke of the pump piston 12. The high point of the cam 37 is in position to hold the valve 33 fully open at the middle of the down stroke of the piston 12 and permits closing movement of the valve 33 during the final one-half of the down stroke of the piston 12. The valve 33, during all of this operation, functions as a baille or atomizer to atomize or increase the atomization of the fuel and the heavy ends of the fuel. Thus the valve 33 is out of closed position during the entire downward movement of the piston 12, which is through 180 of rotation of the crank shaft 1 and of the cam shaft 38.

The distance from the beginning' of the rise to the end of the high part of the cam 50 is about 90, so that the valve 45 does not begin to open until after the valve 33 has been closed.

Cil

more or. less, ofthe crank2..

Thevalve 45 does not begin toy open until: the

.piston` 12has started onthe up stroke, which is duringthe .up stroke ofthe crank 2.r The cam 50 begins .to open the valve. 45 after the crank 2. has moved upwardly about 90, more or less, from. its lowest point and continues to. opensaid .valveduring the next 45. upward movement, Whenthe crank 21 reaches about 135.upv/ardly from vertical, the highes'-'peEnt of the cam 50 passes beyond the valve stem and t c val-fe 45 starts moving Atoward closed position, and. continuesitsmovem ment. toward `closed positionduring the .next 45o upwardmovementof the. crank 2. Atthe end of this movement of the. crank 12, the Valve 45 becomes completely closed. Thus the valve battle '45functions to open thepassage from the pump to. the Working cylinder .after the valve 33 .has closed,..and also functions to further thev 'breaking up. and atomization vofthe .fuel vand the heavyends of the fuel.

Itis now clear that the valve BSisopen only during thedovvn stroke of the pump piston 12 Which, by suction, draws the fuel into the pump cylinder 13, causing' a breaking up and atomiz ing of the fuel and the heavy *endsof the fuel. It isalso clear that, after the valve 33 has closed, the valve 45 is opened .during the turning of the. shafts 1r and 38 throughabout 90, .which is. during the up stroke of. the pump piston .12. The pump piston 12, during up stroke and while the valve45 is open, forces theatomizedand remaining'unatomized fuel across and around the valve 45, thus additionallybreaking up and atomizing theV fueland the heavy enclsof the iuel that had remained unatomized and cooperating with the workingpiston 'I to charge the 'working .cylinder 8 with. atomized combustible fuel'. The .Valves yS3 and 45 cooperate .with their `seatsto form annular passages around the edges .cf'thavalvea and the; annular passage formed by the valve 45 in ycooperation withV itsseat is of smaller `capacity than the passagesV controlled by said valve 45. I have found .that'the effect of this islargely to increase the' atomizing .of-'the heavy fuel. The relativelyjsmall capacity ofthe' annular passage f ormed by. the :valve 45:, is v due to the-.fact that, when said .valve 45. is,open,it is comparatively short. distance from its seat,

thereby: cooperating. with saidv seat to form. `an

annular. passage of small capacity ingcomparison with .the capacity of' thepassaee28-x: 1 p Theiworkine cylinder 8 is formed Withan es:-

vliaust port 51 whichr is opened by the working `piston 7. during thenal portion Vof .the down stroke'v of .said piston if (Figi. 4),. and `oecomes closed, bythe Working pistonA during-the .initial portion of the'up stroke of said piston 7,.and is .continuously closed by the .Working piston thereafter'until said piston Tcompletes' compression .oitl e gas in the Working cylinder, Vanclis again .driven .down- Yby an explosion of4 combustion.

The working piston is the valve'ior the exhaust port. The exhaust port llopensinto .haustl manifold 52.

`.Communication.from the pump cylinder -15 to the working cylinder 1l is similar to thatxfrom the pump piston i3 tothe cylinder 8 above' described; Said communication comprises. a port offavalvefstem'f operates.. The.. relation to andV less volatile-,tl-ianqthe i usual volatile fuels cylindei-.Lll'i .The passage :55. is? of no; greater capacity/thanxthe .end ofv the .passage i541Y connectedthereto.....Tlie ports 56 are'separated, by a .Wallfportionz 5'7r of thecylinder .11 which .functions vto iet the ator'nizedI fueliand` toicomplete atomization of. any small-heavy endsi-of;the...fuel

passing; into .the `.Working .cylinder 11, andas. also functions as a slide surface for the..piston:rngs.

A .poppetvalve .5o/,operates the same as'jithe poppetjvalve 45,.f;beingf;attached"to the. upper end .of a.r valve 'stein 59. f The lower end .ofsthe .stem 59 rengagesa pushrod 61.1: The stem; 59 '.andzpush. rod 6lJ operatein guidesI 60;1and...the `-.push :irod vengages a. 90?;l cam, 62 `sirmlar.t to...the

eam, except that itsrlong radius is. diametrically opposite from the.' long. radius v.of .saidi .cam

,50. There isy rigid on-ztheshaft .38.,.a;.camr63 liketheeam S7, except that itis diametrically opposite, `and on said cam 63 thepush `rod y64 eachgother .ofithe cams .62 and pisv like the .relation to each otherof the cams 37 and. 50.; A valve ste1n65l has a poppet valve attached .to its. upper-.end for. `controlling theyporti.

The push. rod 64 and the Valve 4stem 65 are appropriately guided by guides 65a. andareactu- `ated.downwardly by a yspring 467 while .the valve stem. 59 operated downwardly by a. similar spring GS... y'Ihefcam 63 is.diametricallyfopposite from thecam 37,750 thattlievalve 65 .isialways closed when thevalve 33. is' open, and vice. versa. Obviously, the valves :S3-and 66 areneversiniultaneously open,'nor arethe valves 58 and 45zever `.open at the same time...

An exhaustport 69 from. the cylinder .ll opens intoYtlrle` exhaustgmanifold 52,. It `is now clear that have,y produced panini.-

.proved internal combustion-engine .that will Ql1- erate lsatisfacto1-ly..With vfuels' or fuel oils. heavier such as gasoline, and will cause onjncrease atomization of,;,the heavy.. fuels .or .fueloils durme fthe passage: oiwsaidi fuels. .or :fuel oils :from

the,.carburetor 5to,v the cylinders. 1 The1 valves, 65 and 58 operate. alternately With-and on thegsame timingmrinciple ,asV the .valves 33 and..4.5 andrespectively openanfl yclose.. alternately with the .respective ,said valvesfrand Theseipyalvcs and 45, andfalsotne 4valves.Stand 58., cooper- .ateuwith ,theirl valve: seats to Aform annulaepas- -sasesoiwhch the nassaeesormed by. the. valves 45 and .58 vin:cooiizerati. nwththeir respective valve.' Seats are-Of-wless. area 0r1-capacity2than ,he

.'pasSe-eesinto and from which. Said. annule.. nas:-

sageslopen. The v valves :,ltnemselvesjform' )cailles .to require the atomized Aand partly atomizcd .fuel .to passaround Saidpvalves and' through. Said annular passages, ywith .the result .thatl the heavy vends of. `the fuel are, broken up, and atomization thereofcompletedor increased,i so that theregis lalmost completeatomization ofthe fuel, that .entersjhe Working,.cylinolers.,A

1Q Ato-19; inclusive, tloecranlrv shattfi) has working piston'cranks .7 1 and rIZv/hich are.' 180 from each other, and has pump cranks `'73 andl spaced 183 from each, other.,gTh,e pumpcrank .73 corresponds tothe.. Watkins pist0rizcrank--1-l and is arranged at an angle of 180 therefrom; and the pump crank 74 corresponds to the working piston crank 72 and is arranged 180 therefrom. The working cylinder 75 encloses a working piston 76 connected with the crank 71 by a connecting rod 77. The pump cylinder 78 encloses a pump piston 79 connected with the crank 73 by a connecting rod 80.

The working cylinder 81 encloses a working piston 82 connected with the crank 72 by a connecting rod 83. The pump cylinder 84 enclosesl a piston 85 connected with the crank 74 by a connecting rod 86. Exhaust from the working cylinder 75 passes through an exhaust port 87 into an exhaust manifold 88 and the exhaust from the working cylinder 81 passes through an exhaust port 89 into the exhaust manifold 88. The pistons function as valves to open the respective exhaust ports during the final portions of the down stroke of said pistons, and to close said exhaust ports during the initial portions of the up stroke of said pistons.

The carburetor 90 (Fig. 14) may be of any known or standard construction and is provided with an inlet 91. An outlet pipe 92 from the carburetor communicates through an opening 93 with the manifold 94. The manifold 94 opens into the pump cylinder 78 through a port 95 (Fig. 10). A passage 96 forms communication from the pump cylinder 78 to the working cylinder 75. The top or head member 97 of the engine is formed with combustion chambers 98 above and communicating with the respective Working cylinders 75 and 81; and is formed with chambers 98, which are of less capacity than the chambers 99, above and ccmmunicating with the respective pump cylinders 78 and 84. A passage 100 forms communication from the pump cylinder 84 to the working cylinder 81. The manifold 94 opens into the pump cylinder 84 through a port 101.

A rotary cam shaft 102 is rotated by the crank shaft 70 by means of gearing 103, just like the gearing 43 and 44 above described for rotating the cam shaft 38 by the crank shaft 1.

Two oppositely disposed 180 cams 104 and 105 are attached to the cam shaft 102. A push rod 107 mounted in a guide 108 has its lower end seating on the cam 104 and its upper end arranged to engage the lower end of a valve stem 109 mounted in a guide 110 and having attached to its upper end a Valve 111 controlling the inlet port 95. A similar push rod 112 is mounted in a guide 113 and has its lower end engaging the cam 105 and its upper end arranged to engage the lower end of a valve stem 114 mounted in a guide 115 and carrying on its upper end a valve 116 controlling the port 101. A spring 117 operates the valve stem 109 downwardly, and a spring 118 moves the valve stem 114 downwardly. These cams 104 and 105 are arranged to open the valves 111 and 116 alternately and during down stroke of the respective pump pistons 79 and 85. Two duplicate 55 cams 119 and 120 are attached to the shaft 102. The lower end of a push rod 121 mounted in a guide 122 has its lower end engaging the cam 119 and its upper end engaging the lower end of a valve stem 123 mounted in a guide 124 and carrying on its upper end a valve 125 controlling the inlet to the passage 96 from the pump cylinder 78. The cams 119 and 120 are approximately 55 cams and the angular distance between the long radii of said cams 119 and 120 and long radius of the cam 104 is about 117, more or less. A push rod 126 is mounted in a guide 127 and has its lower end engaging the cam 120 and its upper end arranged to engage the lower end of a valve stem 128 mounted in a guide 129 and carrying on its upper end a valve 130 controlling the discharge from the passage 96 into the working cylinder 75. The valves 125 and 130 open at the same time and close at the same time, but are never open during the time that the valve 111 is open. Nor is the valve 111 open during the time that the valve 116 is open.

rEwo duplicate cams 131 and 132 are attached to the shaft 102. These cams are approximately 55 cams and the angular distance between the long radii of said cams 131 and 132 and the long radius oi the cam 105 is about 117, more or less. A push rod 133 is mounted in a guide 134 and has its lower end engaging the cam 131 and its upper end arranged to engage the lower end oi a valve stem 135 mounted in a guide 136 and having on its upper end a Valve 137 for opening and closing communication from 'the pump cylinder 84 to the passage 100. The valve stem 135 is actuated downwardly by a spring 138.

A push rod 139 is mounted in a guide 140 and has its lower end engaging the cam 132 and its upper end arranged to engage the lower end of a valve stem 141. The valve stem 141 is mounted for sliding movements in a guide 142 and, on its upper end, supports a valve 143 for controlling communication from the passage 100 into the working cylinder 81. A spring 144 actuates the valve stem 141 downwardly. The valves 137 and 143 open at the same time and close at the same time, but are never open during the time that the valve 116 is open. The valve 116 is never open at the same time as the valve 111, nor are the valves 137 and 143 open at the same time that the valves 125 and 130 are open. The valves 125 and 130 are open a part of the time that the valve 116 is open; and the valves 137 and 143 are open a part of the time that the valve 111 is open.

Fig. 12 is a diagrammatic View showing the extent of movement of the working piston cranks 71 and 72 during the times of effective operation of the cams controlling the valves. That is to say, this diagrammatic Fig. 12 shows the positions of the working piston cranks while the respective valves are open. A description of one of the working cylinders and its crank and valve system will sufce for both. The crank shaft 70 turns in a clockwise direction. 1n the position shown in Fig. 12, the piston 76 is on the downward stroke and still closes the exhaust port 87, but will open the exhaust port during the remainder of the down stroke. The axis of the crank 71 for said piston 76 is at the point 145. The valves 125 and 130 begin to open and the opening and closing movements of said valves continue until the crank axis 145 reaches the point 146. That is to say, the valves 125 and 130 are open during the iinal portion of the downward stroke of the piston 76 and remain open during the initial portion of the upward stroke.

The exhaust port begins to open as the axis of the crank moves from the point 145 and remains open until the axis of the crank reaches the point 147.

1t is apparent, however, tha this timing arrangement may be varied within limits without departure from the invention.

From the preceding description and the relevant drawings it is clear that the inlet ports 3l and 56 to the working cylinders 8 and 11, respectively, open into said cylinders through the side walls thereof a considerable distance below the limit of the up stroke of the working pistons 7 and l. The working pistons '7 and 10 cross the inlet ports 31 and 56, respectively, and close said ports when said working pistons complete about one-half of their up strokes. At this point compression begins in the compression cylinders 8 and 11, so that compression is continued in said cylinders 8 and 11 during the final one-half of the up stroke of the working pistons. Thus the working pistons function as Valves to open and to close the inlet ports thereto; and, as previously described and as is apparent from the drawings (Figs. 4 and 5), the working pistons alsoact as valves to open and to close the exhaust ports 51 and 69.

In the embodiment of the invention shown in Figs. 10 to 19 inclusive, the Working pistons 76 and 82 operate with respect to the exhaust ports 87 and 89 in precisely the same Way as the working pistons 7 and 10 operate with respect to the exhaust ports 51 and 69. However, the inlet ports 96 and 100 to the working cylinders 75 and 8l open into the chambers 98 and 99 beyond the up stroke limit of the upper ends or the working pistons. Accordingly, the working pistons '76 and 82 do not function as valves for controlling the inlet ports 96 and 100; but the atomizer valve devices 130 and 143 function as valves to retain the atomized fuel in the working cylinders during the compression strokes of the working pistons. The valves may be otherwise arranged than as specifically shown and described.

It is now clear that I have produced an internal combustion engine embodying many novel features of construction and arrangement which will be apparent from the foregoing description and the annexed drawings. Because of the novel construction and arrangement and operation oi" the devices embodied in this invention, I am enabled to use heavy fuel oils as distinguished from the usual volatile fuels, such as gasoline. The valves are arranged in a manner to baffle the passage of the fuel to the pumps and from the pumps to the working cylinders. The invention is not dependent upon the use of poppet valves, as other types of valves might be used with equal satisfaction. An important feature of the invention consists in the arrangement and operation of valves to baffle and break up and atomize the fuel and the heavy ends of the fuel passing from the carburetor to the pump and from the pump to the working cylinders. Different types of valves may be used for this purpose.

I contemplate any variations that may be found useful in the construction of the engine,

'or that will contribute to its efficiency. I do not restrict myself in unessential respects, but what I claim and desire to secure by Letters Patent is:

1. An internal combustion engine comprising a body, parallel working and pump cylinders in said body, a headattached to the upper end of said body and having a combustion chamber above said working cylinder and a chamber of less capacity than said combustion chamber above said pump cylinder, means forming an inlet passage to said second chamber, a transier passage from said second chamber to said Working cylinder, valves mounted in said second chamber controlling said passages respectively, and mechanism for opening and closing said valves alternately, each of said valves being opened for a different duration of time than the other and after theother is closed.

2. An internal combustion engine comprising parallel working and pump cylinders, a head attached to vand closing the upper ends of said cylinders and having chambers above and comy municating with said cylinders respectively, the capacity of said chamber above the working cylinder being greater than the capacity of said chamber above the pump cylinder, means forming an inlet passage to said chamber above said pump cylinder, an outlet passage from said chamber above said pump cylinder to said working cylinder, valves mounted in said chamber that is above said pump cylinder cooperating with said inlet and outlet passages respectively and to form openings of less capacity than the capacity of said respective passages, and means for opening each or" said valves for a diierent duration of time than the other valve is opened and after said other valve is closed.

3. An internal combustion engine comprising parallel working and pump cylinders, a head attached to and closing the upper ends of said cylinders and having chambers above and coinmunicating with said cylinders respectively, the capacity of said chamber above the working cylinder being greater than the capacity of said chamber above the pump cylinder, means forming an inlet passage to said chamber above said pump cylinder, an outlet passage from said chamber above said pump cylinder to said Working cylinder, valves mounted in said chamber that is above said pump cylinder cooperating with said inlet and outlet passages respectively and to form openings of less capacity than the capacity of said respective passages, and means for opening each of said valves for a diierent duration of time than the other valve is opened and after said other valve is closed, said valve controlling said passage to said working cylinder opening against the pressure in said pump cylinder.

CHARLES LATTA. 

